OSX 10.8.4 SATA-3 Motherboard, SSD SATA-3 works only at 3Gb/s

[Marxy]

Motherborad GIGABYTE GA-X79-UD3
Graphics NVIDIA GeForce GT 640 2048 MB
CPU 3.7 GHz Intel Core i7
Memory 2x8 GB 1600 MHz DDR3
OSX 10.8.4
SSD Sandisk Ultra Plus FW: 2306RL

Today I bought SSD, setted it up to computer but in the System informations I see only 3Gb/s.
Motherborad for sure is SATA-3 enabled because of my regular disk works fine at 6GB/s

Product: AHCI Standard Controller
Link Speed: 6 Gigabit
Negotiated Link Speed: 6 Gigabit
Description: AHCI Version 1.30 Supported
Model: WDC WD10EALX-008EA0
Revision: 05.01D05

But fo Sandisk System Info is

Product: AHCI Standard Controller
Link Speed: 6 Gigabit
Negotiated Link Speed: 3 Gigabit
Description: AHCI Version 1.30 Supported
Model: SanDisk SDSSDHP128G
Revision: X2306RL

Why this happened? All the ports on the motherboard are SATA-3. AHCI enabled.

 

[Marxy]

Strange, but solved. I've moved SSD to another SATA-3 port. Not it is 6/6.

It is strange because of the recent port was (it is seen at the previous port) SATA-3 6Gb/s too...